In an appearance on "The Ellen DeGeneres Show," which will air today, Mendes, 39, poked fun at reports that she and Gosling, 33, are no longer an item.
Asked by DeGeneres if she had any Valentine's Day plans, Mendes replied, "I'm not a big Valentine's Day person. I'll probably just order a deep dish and watch 'The Notebook' or something."
The actress was referring to Gosling's 2004 mushy romantic drama, in which he starred opposite ex-girlfriend Rachel McAdams.
Mendes and Gosling have been dating since the fall of 2011. But after not being photographed together since last October, talk began to surface that the ultra-private couple had split.
Gosling seemed to dispel those reports Sunday when he was snapped solo behind the wheel of Mendes' SUV in Los Angeles.
As for those other reports that Mendes is pregnant with Gosling's baby, the actress kept her sense of humor when DeGeneres asked about them.
"It's so ridiculous," Mendes said. "It all started because I didn't want to go through those X-ray scanners at the airport, which are really creepy. They basically see you naked, right. And not only that, but there's a radiation aspect to it. So I always opt out. I always ask for a personal pat down."
"Good idea," DeGeneres responded, drawing laughter and applause. "That's the way you get a Valentine."
Check out the video below.